Heart chamber (such as atrium and ventricle) hemodynamic blood output is used to diagnose and characterize heart arrhythmias and pathologies, such as atrial fibrillation and left ventricle myocardial ischemia. Chamber blood output is a measure of the blood ejected by a cardiac chamber, such as a left ventricle in one minute or in one heart beat, and is an important vital sign for patient cardiac function and health status monitoring. There are different methods used to calculate chamber blood output, such as calculation and characterization based on a blood pressure waveform, thermodilution, bio-impedance, pulse contour and ultrasound method, for example. However most of these clinical methods are invasive and not reliable and have application limitations including complexity, timing problems, sensitivity and generation of false alarms, for example.
The cardiovascular system comprises, a pump—the heart, a carrier fluid—blood, a distribution system—the arteries, an exchange system—the capillary network, and a collecting system—the venous system. Blood pressure is the driving force that propels blood along the distribution network. Chamber blood ejection volume is the volume of blood pumped by the right and left atrium and ventricle of the heart in one contraction. Specifically, cardiac output comprises volume of blood ejected from ventricles during a systole phase. The blood ejection volume is not all of the blood contained in the cardiac chamber. Normally, only about two-thirds of the blood in the cardiac chamber is put out with each beat. What blood is actually pumped from the cardiac chamber is the chamber blood flow volume and it, together with the heart rate, determines the chamber blood output. There is a lack of efficient and low cost known external non-invasive measuring, estimation and calculation systems using NIBP (non-invasive blood pressure) and ECG signals for cardiac chamber blood flow output and volume determination, especially for emergencies.
Accurate hemodynamic measurement and parameter calculation, is needed to monitor and characterize patient health status. Accuracy of known chamber blood calculation of CO (cardiac output) and SV (stroke volume) for a left ventricle is typically impaired due to blood pressure measurement in a noisy environment, or measurements derived using image scanning and acquisition with imprecise timing. Additionally, known systems are typically based on invasive signal acquisition and data measurements and fail to provide accurate chamber blood output analysis and health parameter calculation. Such known systems involve need for, blood samples for Fick cardiac output measurement, images of EoD (end of diastolic) and EoS (end of systolic) phases in angiographic procedures for cardiac output calculation, and deviation of measurement data in thermodilution based cardiac output monitoring, for example. Known less-invasive or non-invasive methods for chamber blood output estimation attempt to utilize blood stroke volume within local vessels to proportionally estimate the heart SV (stroke volume). The nonlinear relationship between measurement and actual heart chamber blood output may result in substantial calculation errors and false alarms in monitoring, especially in critical care monitoring and lead to inaccurate diagnosis.
Known hemodynamic signal analysis, such as cardiac output and stroke volume estimation, usually utilizes one chamber output, such as left ventricular CO, to estimate the cardiac function. Known systems typically fail to use multi-chamber blood output data for determination of cardiac arrhythmias and pathology, for example. A system according to invention principles addresses these deficiencies and related problems.